Reverberatory smelting and refining furnace



(No Model.) 2 Sheets-Sheet 1.

v B. HALL. REVERBERATORY SMELTING AND REFINING FURNACE. No. 589,210.Patented Aug. 31,1897.

2 Sheets-Sheet 2,

(No Model.)

B. HALL. REVERBERATORY SMELTING AND REFINING FURNACE.

No. 589,210. Patented Aug. 31,1897.

U TED ST TES PATENT" OEFIE.

BENJAMIN HALL, OF NEVADA CITY, CALIFORNIA.

REVERBERATORY SMELTING AND REFINING FURNACE.

SPECIFICATION forming part of Letters Patent No. 589,210, dated August31, 1897.

Application filed f'ehruaryiflil e91: se rialj to. 623,812. (No model.)

. zen of the United. States, residing at Nevada City, Nevada county,State of California,have invented an Improvement in ReverberatorySmelting and Refining Furnaces; and I hereby declare the following tobea full, clear, andv exact description of the same.

My invention relates to improvements in reverberatory smelting andrefining furnaces which are especially useful in the treatment ofpyritic ores.

It consists in the parts and the constructions and combinations of partshereinafter described and claimed.

Figure 1 is a vertical longitudinal section of my apparatus. Fig. 2 is ahorizontal-section on line x as of Fig. 1. Fig. 3 is a view of the feedend. Fig. at is a section on line y y of Fig. 2. Fig. 5 is a View of thefeed-trough.

In the working of reverberatory furnaces the ore is usually fed incharges, s1nelted,the slag skimmed off, another charge put in until asufficient amount of metal or matte ha'saccumulated, when it is tappedand drawn off. The disadvantage of this method is that the matte ormetal is covered with a layer of ore or slag that cannot be penetratedby the airblast. Therefore it is not oxidized and concentrated, and thefuel qualities of such oxidation are not utilized.

In my invention the furnace proper, A, is made inthe usual or anysuitable form for this class of furnace, having at the receiving endblast-pipes B and a feed device, whichwill be hereinafter described, andat the op-' posite end the furnace is contracted to a narrowdischarge-opening C, havinga bridgewall D, over which the slag isconstantly discharged by natural flow and by the'action of the blast andis delivered into a smaller supplementalfurnace-chamber E, from whichthe slag is finally discharged over .a bridge. F. The furnace may alsohave the usual. tapholes A, as shown in Figs. 1 and 2.

The escape-flue or chimney G is situated at the end of the supplementalchamber E, so

- that the heat and products of combustion after leaving the mainchamber A will pass into and through the supplemental chamber E, wherethe accumulated matte and slag from the main chamber are still exposedto the heat and prevented from too rapid cooling. By means of the twosuccessive chambers, arranged as shown, the matte: which results fromthe smelting of the ore first sinks to the bottom of the mainsmelting-chamber and follows this chamber up to a level with the top ofthe discharge top of the wall D and the discharge-opening O. Thereafterthe slag will constantly flow over into the chamber E.

The uniform level of the matte maybe varied by the insertion ofwater-pipes d trans- Versely within the wall D, and an increase ordecrease of the flow of water through these pipes raises or lowers thelevel of the matte. The slag which is formed upon the top of the mattebeing in a fluid condition will flow over the wall D and constantlymaintainan even level surfaceof' the matte without being covered orburied too deeply in the slag, and the blast which was admitted throughthe pipes assists to carry the light slag along and discharge it andleave the matte constantly eX- posed to the air-blast.

The matte is drawn off from time to time from the supplemental chamberE, while the slag is allowed to pass off through the opening F. By thiscontinued double operation, if used upon ore which might run, forinstance, five per cent. of copper, the concentration would be such thatthe matte drawn off from either chamber A or E would run as high asfifty per cent. of.copper, and from this it would be easy to conveyitinto a second similar furnace or refining apparatus,

such'apparatus having a tilting ladle or furnace in place of the feedingdevice herein described.

The feeding device of my furnace consists of an approximatelyhorizontaltrough H, having a rotary screwv journaled to turn in it, so that themewhich is delivered to the trough" at one end will be gradually advancedby this screw. This trough H extends across the end of the furnace at asufficient height, so that the branch troughs or chutes I, lead;- ingfrom it, at intervals will receiveftheore from the screw which iscarrying it along behind the troughs, and each chute will thus besupplied with a portion of the ore which slides down into the receivingend of the fur vent the dissipation in nace. These chutes I are madewith receiving-openings I from the many troughs inclining from one sideto the other. This construction is better suited to distribute the oreevenly from the transverse main trough I'I into these chutes from oneside to the other, so that it will flow down over the full width of thebottoms of the chutes. These inclined edges incline in line with eachother, as shown, until the last but one terminates at the floorlevel ofthe trough II.

The last one of the chutes I is fed by an opening in the bottom of thetrough II, as shown, so that the ore will be delivered regularly fromone side of the receiving end of the furnace to the other.

The angle of the blast-pipe I is such that the blast of air from thesepipes does not strike the ore until it has moved a short distance awayfrom the end of the f urnaee toward the center, and by the time theblast does strike it it has become heated, so that it will more readilyburn, and to such an extent that it will in a way cement together andthus prethe form of dust when the blast strikes it. These blast-pipesare adjustable to change the angle of any one or more of them, so thatthe blast strikes the ore nearer to or farther from. the receivingend,as may be desired.

A supplemental blast-pipe or oil-burner enters the upper part of thefurnace, as shown at .I, or above the surface of the ore and matte, andalso discharges upon the mass of ore within the furnace at a point inadvance of that of the blast-pipes B.

A cold blast may be employed, if preferred, or the pipes connecting withthe blast-pipes B may be carried through the walls of the furnace abovethe level of the surface of the matte, whereby the air is heated withinthese pipes. A line of water-pipes K along the level of the matte keepsa certain temperature along this line which prevents the lining of thefurnace from being entirely destroyed by the slag.

In some cases where a suitablehydrocarbon oil is obtainable theair-blast may be joined with oil-jets, but where this is not used I haveshown a furnace K, built at one or both sides of the main furnace A andhaving a fine or opening at L, through which the heat and products ofcombustion pass into the main furnace A to assist in smelting the oretherein or to commence the work or to heat the air for the jets, theamount of sulfur in the ore being usually about sufficient for the workafter it has once begun.

Having thus described my invention, what I claim as new, anddesire tosecure by Letters Patent, is-

1. A horizontal reverberatory smelting-fu rnace having a feed mechanismat one end and a discharge at the opposite end, said feed mechanismcomprisinga series of chutes leading into the furnace and afeed-screwwhereby the ore is delivered successively to the chutes and thence tothe furnace.

2. A horizontal-hearth smelting-furnace having a series of chutesleading into one end thereof and a feed-screw whereby the ore isdelivered regularly and continuously at the receiving end, a passagethrough which the slag is discharged at the opposite end and a blastapparatus delivering air in at the receiving end along the line oftravel of the ore.

3. A horizontal-hearth reverberatory furnace having a feed-inlet and afeed-screw at one end, a discharge at the opposite end and a blast-inletat the receiving end along the line of travel of the ore whereby theaction of the draft skims the slag from the matte-or metal.

4. In a horizontal-hearth reverberatory furnace, a continuous feeddevice comprising a series of chutes leading into the furnace and afeed-screw delivering ore successively to the chutes whereby the ore isdelivered at one end of the furnace, a discharge-passage at the oppositeend, the blast pipe or pipes delivering the air into the feeding end ofthe furnace along the line of travel of the ore, a supplementalfurnace-chamber in line beyond the discharge adapted to receive theoverflow of slag and matte whereby the level of the matte isapproximately maintained, a chimney or stack at the outer end of thesecond chamber through which the products of combustion escape afteracting upon the matte and slag within said chamber, and a finaldischarge-passage for the slag at the end of said chamber.

5. In. combination with a horizontal reverberatory furnace, a mechanismfor regularly feeding the ore thereto consisting of a trough extendingacross behind the feed end of the furnace, a screw revolving in saidtrough to advance the ore transversely, inclined chutes opening from themain trough and having their receiving-openings inclined from one sideto the other, said chutes each receiving a supply of ore from therotating screw and delivering it into the rear of the furnace.

6. A horizontal reverberatory furnace, a transverse trough extendingacross behind the receiving end of the furnace, a series of inclinedchutes leading therefrom into the furnace, said chutes having partitionsat the receiving ends inclined transversely so that one edge is lowerthan the other, and a: revolving feed screw journaled in the maintransverse trough whereby the ore is carried along said trough anddelivered successively to the inclined chutes and thence to the furnace.

In witness whereof I have hereunto set my hand.

BENJAMIN I'IALL.

\Vitnesses:

S. II. NoURsE, JESSIE 0. 1311011112.

